Field of the Invention
The present invention relates to an internal combustion engine for a vehicle in which an engine main body having a cylinder head is mounted on a vehicle body frame, and an exhaust muffler to which exhaust gas from the cylinder head is guided extends in a vehicle width direction and is disposed on a rear portion of the vehicle body frame, and particularly to an improvement in an exhaust system structure.
Description of Related Art
An exhaust system structure of an internal combustion engine for a vehicle is already known in Japanese Patent Laid-Open No. 2014-141161 in which structure a catalytic device is connected to an exhaust muffler, which extends in a vehicle width direction and is disposed on a rear portion of a vehicle body frame, from the front of the exhaust muffler to form substantially the shape of a T.
In the vehicle disclosed in the above-described Japanese Patent Laid-Open No. 2014-141161, a rear floor is provided on the rear portion of the vehicle body frame so as to be disposed above the exhaust muffler and the catalytic device. A measure is thus necessary for insulation from heat from the exhaust muffler and the catalytic device to the rear floor. In that case, it is desired that a heat insulating property be enhanced while a complex heat insulating structure is avoided.